Added further instructions for multiline test cases.
Keep test filename inline with rule name

`dot-notation` is `dot-notation` in `eslint.json` and the rule is at `lib/rules/dot-notation.js`. This change just keeps the rule test named the same as the rule it represents.
Rename test for smartereqeqeq.js to smarter-eqeqeq.js

Keeping test file name inline with rule name and rule filename.